Wide Cushioned Cable Tie for Optical Fiber Bundle

ABSTRACT

A wide bodied cushioned cable tie for use with securing optical fiber bundles is formed of a sturdy polymer e.g. polyethylene with a strap width of about one inch and with broad longitudinal flanges on either side of the rack of teeth on the strap. Neoprene foam cushions extend along each of the flanges. The ratchet or pawl can be provided with a release tab. A service opening at the tip or tail of the strap facilitates hanging the bundle from support structure.

BACKGROUND OF THE INVENTION

This invention is directed to articles used in binding articles, e.g., bundles of wires or cable, and is more specifically directed to the self-latching banding items known in the trade as cable ties, and also sometimes called zip ties or tie-wraps.

Cable ties are often used for binding a number of electronic of optic fiber cables together for purposes of organization and support.

The familiar cable tie consists of a sturdy plastic strap, i.e., a tape or band (typically nylon) with an integrated gear rack or series of saw-tooth shaped members along one side. The tip of the cable tie fits into a slot or channel or tunnel in a wide head portion at one end of the tie, and this allows the strap to be pulled through the head. A ratchet member, i.e., a pawl, engages these teeth and prevents the strap from being pulled out in the reverse direction, although in some cable ties a tab or similar member attached to the pawl allows the installer to release the pawl.

The strap is sometimes called the “tail”, and in some permanent installations the part of the tail that extends out beyond the “head” can be cut or trimmed.

The cable ties used in communications and electrical applications can have a strap length of any size. However, these items usually have a width dimension of about ⅛ inch up to bout ¼ inch. The main strap or band of the cable tie is flexible, but nearly rigid, and incompressible. Where these cable ties are used for bundling delicate or fragile items, e.g. cables containing optical fibers, there is a risk that the cable tie can cut into the item and can sever or otherwise damage the optical fiber.

One way of addressing this issue has been to use multiple cable ties instead of only a single cable tie at each area where the bundle of fiber optic cables is to be bound. This technique distributes the pressure of the cable ties over a number of units. However, in this arrangement some of the cable ties will invariably be tightened more than others, and can still crush or damage individual optic fibers within the bundle.

OBJECTS AND SUMMARY OF THE INVENTION

Accordingly, it is an object of this invention to provide an improved cable tie for use in fiber optic systems, for binding together a group of cables each containing a number (one or more) of optical fibers, and which avoids structure that could damage the optical fibers.

More particularly, if is an object to provide a cable tie which distributes pressure on the bundle of optic fibers over a wider area than is possible with traditional cable ties.

It is another object to provide a measure of cushioning between the band or strap of the cable tie and the bundled cables.

If is also an object to provide the cable tie as a removable, re-usable article.

A further object is to provide means in the cable tie to permit it to be suspended from or affixed onto a support member.

The present invention involves a cable tie for use in bundling optical fiber cables. Pressure from the cable tie is distributed over a wide area on the bundle of optical fiber cables. The cable tie comprising a head, an elongated flat strap, a neck portion joining the head to the strap, and a tail end of the strap remote from the head. The strap has an outer side adapted to face away from the optical fiber cables of the bundle and an inner side adapted to face towards and to contact the optical fiber cables. The strap has a rack of teeth on its inner side, extending between the neck portion and the tail end. There are longitudinal flanges extending along either side of said rack of teeth. The head has a tunnel dimensioned to accommodate the strap and to permit the tail end and at least a portion of the strap to be pushed through, and the a pawl member formed at the tunnel to engage the teeth to hold the strap in place in the head.

In a preferred embodiment, the strap has a lateral width of substantially an inch, and the strap includes resilient foam cushions disposed on each of the longitudinal flanges. The foam cushions contact against the bundle of optical fiber cables when said cable tie is in place over the bundle.

Favorably, the pawl member has a set of teeth adapted to engage the teeth of the rack. A spring hinge urges the teeth towards the teeth in the rack yet permits the teeth to deflect so that the rack can be inserted in said tunnel past said pawl member. A release tab extends out from said tunnel, and allows the installer to push the pawl out of engagement with the rack of teeth so the strap or band can be pulled out of the cable tie head to remove the cable tie.

Favorably, the head and the strap are formed of a stiff, flexibly resilient polypropylene, and the flanges and foam cushions each have a width of substantially one-eighth inch. The foam cushions are favorably formed of a neoprene foam, and these cushions can extend over at least a majority of the length of flanges between the neck portion and the tail portion.

The tail end can have a taper of between about 5° and 10°, and can be provided with a through hole that permits the tie and any associated bundle of fiber optic cables to be suspended from a suitable support structure. That is this hole permits the article to be hung from a screw, or nail, or hook.

This wide, cushioned cable tie of this invention may be employed in other applications as well where the traditional cable tie would seem to have some drawbacks, such as in medical, industrial or automotive applications.

An embodiment of the connector holder of this invention is illustrated in the attached Drawing figures.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of the cable tie of this embodiment, showing the device in place binding a number of cables into a single bundle.

FIG. 2 is a top plan view of the cable of this embodiment.

FIG. 3 is a side elevational view thereof.

FIG. 4 is a bottom plan view thereof.

FIG. 5 is a cross sectional view of this embodiment take at line 5-5 of FIG. 1.

FIG. 6 is a cross sectional view taken across the axis at lines 6-6 of FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to the figures of Drawing, FIG. 1 illustrates a cable tie 10 according to an embodiment of this invention, here securing a bundle 20 of optical fiber cables. The cable tie 10 has an elongated band or strap 12 with a head 14 at one end joined by a neck 16 to the strap, and a tip or tail end 18 that extends through a tunnel or channel 22 in the head 20 of the cable tie. The strap 12 forms a loop that closes around the bundle 20 and is pulled tight to secure the bundle.

As illustrated in the top, side, and bottom views of FIGS. 2, 3, and 4, and in the sectional views of FIGS. 5 and 6, the band or strap 12 has a generally smooth surface on its upper side, i.e., the side that faces away from the bundle 20, and gripping structure (to be described shortly below) is incorporated onto its lower side, i.e., the side that faces against the bundle 20. Within the tunnel or channel 22 in the head 14 is a ratchet mechanism or pawl 24, having a set of teeth 26 on a proximal surface and having a resilient hinge portion 28 at the inner or lower side of the tunnel or channel 22, i.e., seen in FIG. 4. A release tab 30 extends out beyond the outer or upper side of the head 14, and allows for release of the pawl from engagement with a rack of teeth 32 that are incorporated onto the lower side of the strap 12 so that the cable tie may be loosened or removed, if necessary. This avoids the need to cut the cable tie, and avoiding damage to the optical fibers which could result from contact with a sharp blade.

As seen in FIGS. 1, 4, and 6, the cable tie has a rack or row of sawtooth shaped elements, i.e., teeth, here shown as the rack 32, that extends along the mid portion of the strap 14 at its lower side from the neck 16 to the tip or tail end 18 of the strap. Along either side is a fairly broad, flat longitudinal flange 34, and on each flange are respective longitudinal cushion members 36, each formed as a layer of a neoprene foam material.

In this embodiment, the band or strap 12 has a width of substantially one inch (i.e., 2.54 cm), with the rack 32 having a width of about one-half inch, and each of the flanges 34 being about one-quarter inch in width. The cushions are likewise one-quarter inch in width. The cushions may favorably have a thickness on the order of about 1/64 inch to 1/16 inch. As indicated by the bent cut lines in FIGS. 2, 3, and 4, the strap portion 12 can be of any length suitable for the intended application. The tunnel or channel 22 is dimensioned slightly larger than the strap, i.e., with a width of 1 1/16 inch, to accommodate the strap and allow it to pass through so that the pawl 24 will engage the teeth of the rack 32. In this embodiment, the strap and head are unitarily formed of a suitable polypropylene resin, which may include suitable additives for strength and resiliency. Other resins may be used, as may be appropriate for a given application. For example, a nylon composite resin could be used to advantage in some cases. The material used should be fairly stiff but flexible enough to encircle the fiber optic bundle. Also, the strap may be made somewhat wider or narrower than the described embodiment, without departing from the main principles of this invention, also depending on the intended application.

In this embodiment, the tip or tail end is provided with a taper of between about five and ten degrees, i.e, the angle between the edges and the center line as seen in FIGS. 2 and 4, and here the taper is approximately six to seven degrees. A thickness taper may also be provided, as seen in FIG. 18.

A utility opening, i.e., a through hole 38 is provided in the tail end near the distal tip, and this may be used to hang the cable tie 10 and its associated bundle 20 from building structure, i.e., a wall or support stud, using a convenient screw fastener or hook. In this embodiment, there is a single through hole 38 of about 5/16 inch diameter. However, there may be more than one hole provided, and the size and shape of the hole(s) may vary.

Returning to FIG. 1, is should be appreciated that the cable tie 10 of this embodiment provides a secure and non-damaging way of binding the bundle 20 of optical fiber cables, as its wide flanges 34 spread the contact of the strap 12 over a wide area, and the cushions 36 prevent the strap 12 from cutting into the cables or crushing and damaging them. The neoprene foam material also assists in gripping of the bundle 12, which allows less tension to be required in the cable tie to secure the bundle.

The cable ties may be fabricated in various colors as well for purposes of identifying specific bundles of fiber optic cables.

While the invention has been described with reference to one embodiment, the invention should not be limited only to that embodiment. Many variations are possible within the scope of invention as defined by the appended claims. 

I claim:
 1. Cable tie for use in bundling optical fiber cables in which pressure from the cable tie is distributed over a wide area on the bundle of optical fiber cables, the cable tie comprising a head, an elongated flat strap, a neck portion joining the head to the strap, and a tail end of the strap remote from said head, the strap having an outer side adapted to face away from the optical fiber cables of the bundle and an inner side adapted to face towards and to contact the optical fiber cables, said strap having a rack of teeth on its inner side and extending between said neck portion and said tail end, with longitudinal flanges extending along either side of said rack of teeth; said head having a tunnel therein dimensioned to accommodate said strap and to permit said tail end and at least a portion of said strap to be pushed therethrough, and having a pawl member formed at said tunnel to engage said rack of teeth to hold said strap in place in said head; wherein said strap is formed with a lateral width of substantially one inch, and said strap includes resilient foam cushions disposed on said longitudinal flanges respectively, such that the foam cushions contact against said bundle of optical fiber cables when said cable tie is in place over said bundle.
 2. The cable tie of claim 1, wherein said pawl member a plurality of teeth adapted to engage the teeth of the rack, a spring hinge urging said plurality of teeth deflectably towards said rack but permitting the rack to be inserted in said tunnel past said pawl member, and a release tab extending out from said tunnel.
 3. The cable tie claim 2, wherein head and said strap are formed of a stiff, flexibly resilient polypropylene.
 4. The cable tie of claim 1, wherein said flanges and said foam cushions each have a width of substantially one-eighth inch.
 5. The cable tie of claim 1, wherein said foam cushions are formed of a neoprene foam.
 6. The cable tie of claim 1, wherein said foam cushions extend over at least a majority of the length of said flanges between said neck portion and said tail portion.
 7. The cable tie of claim 1, wherein said tail end is provided with a through hole adapted for hanging said tie and an associated bundle of fiber optic cables from a suitable support structure.
 8. The cable tie of claim 1, wherein said tail end is provided with a taper of the order of about 5 to 10 degrees. 